There are numerous reasons for the errors 19 and 24 but both of these errors can relate to hard drive faults. I would first check your hard drive with the manufacturers diagnostics. Follow this guide:

Identify the make of your hard drive and then use one of the links below to get the manufacturers diagnostic for ISO CD. Burn the image file to a CD, boot the PC with the disc in the drive and run the diagnostics. You first need to set the CD drive to 1st in the boot order in the Bios setup.

If you do not have an image burner use this free software to make the CD.

If the above comes up clear then run Driver Verifier to check all your systems drivers.

For windows XP - Click on Start and then Run. Type verifier into the box and hit the Enter key.
For Vista and Windows 7 - Click on Start and type verifier into the search box then click on verifier in the list that pops up.

Driver Verifier Manager will open.

Select the first choice "Create Standard Settings" and click on the "Next" button.

Now select "Automatically select all drivers installed on this computer" and click on the "Finish" button.

A box will appear asking you to restart the PC for the changes to take effect. Click on "OK" and reboot the PC.

To stop Auto reboot so you can read the error message do this for Windows XP:
Click the Start button, right-click My Computer, click Properties, click the Advanced tab, and then click Settings under Startup and Recovery.
Under System Failure, uncheck the "Automatically restart" check box.

And do this in Windows 7 and Vista:
Click Start, select 'Control Panel' select 'System' in the left pane select 'Advanced System Settings' in the box select the 'Advanced' tab then under 'Startup and Recovery' select 'Settings.' In the box under 'System Failure' uncheck 'Automatically Restart'.

If the PC reboots normally then there is no problem with any of the drivers. If you get a blue screen straight away it will name the faulty driver. If you are absolutley certain that the named driver is OK then make a note of it.

You will then have to go back into the Verifier and instead of selecting all drivers select "Select drivers from a list". Click on "Next" and the list of drivers will appear. Select them all apart from the one you know to be OK. Click on "Finish" and reboot.

Once you have identified the faulty driver or confirmed that there are none go back to the first page of the Driver Verifier Manager and select "Delete Existing Settings" and click on "Finish"